When Joshua Bell was 21, he recorded an iconic piece of chamber music for piano and violin — the Sonata in A major by Cesar Franck. Today, Bell is 44 and he's recorded it again. It's on his new album, French Impressions, with pianist Jeremy Denk.

All Things Considered host Robert Siegel invited Bell to listen to his old recording for a little session of compare-and-contrast.

"Do you hear the same violinist?" Siegel asks, after playing for Bell the opening bars of his 1989 recording.

"It's not as bad as I thought it was," Bell says. "But then my next impression is, I could have done a lot more here in this harmony, and I could have followed some of the instructions in the score a little bit better."

In other words, Bell hears major differences in his playing some 22 years ago.

"This music is very subtle. There are so many beautiful harmonies that, if you indulged in every one, you'd lose the scope," he says. "And yet some of the beauty of French music is that there are moments that you don't think about the overall structure and you enjoy the beauty of that moment."

What's the relationship like between Bell and a piece like the Franck Sonata, which he's continued to play for several decades?

"I'm still the same basic human being," he says, "but I feel I know the piece so much better. I've internalized it so much more — the way it's paced. Hopefully, I'm bringing out much more nuance and more color and things I've discovered in the piece since. You're a constant student, as a musician."

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